This invention relates to a hydraulically actuable braking apparatus.
More particularly the invention relates to a hydraulic brake of the type disclosed in German Patent DE No. 31 44 868 Cl. In that braking apparatus an annular groove is provided at the ends of the piston which protrude from the cylinder and a plane metal ring with several tongues bent somewhat out of the radial plane are disposed in the groove.
This ring and piston structure suffers from the shortcoming that, especially during assembly and maintenance of the brake, it is possible that the metal ring will be ejected out of the seat within the annular groove due to, for example, imposition of a force or torque acting on the metal ring. Particularly because of the plane design of the metal ring, it is also possible that the ring will be moved out of the groove by a lever force due to insertion of a tool or some other object into the gap between gasket and metal ring.